2 definitions
by
ahrien

Used to indicate that a person has definitively beaten the opposition in a given situation. Derived from the game of tennis in which the winner of a match is the player who wins two out of three (for women) or three out of five (for men) sets; each set is made up of a number of games. Thus, the final winning shot is the one that wins the player the point that wins the game that wins the set that wins the match.

"When the prosecutor pulled out the security cam photo showing Darryn in the convenience store with the gun, they had him game, set, match."